Heat-assisted permanent waving system

ABSTRACT

A heat-assisted ammonium thioglycolate permanent waving system is provided in which heat-containing clamps applied to the hair to assist the action of the ammonium thioglycolate bring the hair up to hair waving temperature and maintain it at such temperature for no more than 6 minutes and in which the ammonium thioglycolate solution is weaker than is used in non-heatassisted permanent waving for the same type of hair and stronger than has been used in prior heat-assisted permanent waving for the same type of hair.

Edelberg et a1.

HEAT-ASSISTED PERMANENT WAVING SYSTEM Inventors: Norman L. Edelberg, DesPlaines;

John R. Forsberg, Arlington Heights, both of I11.

Assignee: Helene Curtis Industries, Inc.,

Chicago, 111.

Filed: Jan. 11, 1974 Appl. No.: 432,597

US. Cl 132/7; 424/71 Int. Cl A45d 7/00 Field of Search 132/7, 31, 33;424/71;

References Cited UNITED STATES PATENTS 8/1946 Rood et a1. 132/31 1451May 27, 1975 2,621,280 12/1952 Judd ..219/24 3,583,408 6/1971 Wall 132/73,736,944 6/1973 Ghilardietal ..132/7 Primary Examiner-G. E. McNeillAttorney, Agent, or FirmDressler, Goldsmith, Clement & Gordon, Ltd.

[57] ABSTRACT A heat-assisted ammonium thioglycolate permanent wavingsystem is provided in which heat-containing clamps applied to the hairto assist the action of the ammonium thioglycolate bring the hair up tohair waving temperature and maintain it at such temperature for no morethan 6 minutes and in which the ammonium thioglycolate solution isweaker than is used in non-heat-assisted permanent waving for the sametype of hair and stronger than has been used in prior heatassistedpermanent waving for the same type of hair.

5 Claims, N0 Drawings HEAT-ASSISTED PERMANENT WAVING SYSTEM Thisinvention relates to a system for the permanent waving of hair in whichan ammonium thioglycolate solution of controlled strength is utilized inconjunction with the application of heat at a controlled temperature andfor a controlled period of time.

The permanent waving of hair is commonly carried out by applying to thehair. while it is wound around rolls, an aqueous solution of ammoniumthioglycolate to soften the hair strands, followed by removal of excessthioglycolate solution and then by application of an oxidizing solutionto the hair to neutralize the ammonium thioglycolate solution and torestore firmness to the hair strands. Substantially all permanentwavingfor home use and much of the permanent waving in beauty shops isof the cold wave type in which no external heat is used. Such permanentwaving takes a substantial time to effect despite the fact thatrelatively strong ammonium thioglycolate solutions are used.

To reduce the time necessary to effect a permanent wave external heatmay be applied to the hair while it is wound around the rolls,preferably by the application to each roll of a preheated clamp ofsufficient heat capacity to maintain the hair within a desiredtemperature range for a sufficient time to permit the ammoniumthioglycolate to effect its desired action. With such heat-assistedpermanent waving, ammonium thioglycolate solutions of lesser strengthare used than are used in non-heat-assisted permanent waving for hair ofthe same type.

Because of the rapidity of the action of the ammonium thioglycolatesolution when heat-assisted, it is necessary to control the time of itsaction to avoid overprocessing and consequent damage to the hair. Theoperators in such heat-assisted permanent waving are instructed to limitprocessing time but sometimes fail to do so.

In accordance with the present invention the heat content of the clampsand the strength of the ammonium thioglycolate are correlated so thatthe clamps cool within the appropriate processing time to a temperatureat which the ammonium thioglycolate solution loses substantially all ofits processing activity. Specifically, the construction and material ofthe clamps and the temperature to which they are preheated are selectedto permit the clamps to heat the wetted hair on the rolls to atemperature about 120F. and to maintain a temperature above 120F. for nomore than 6 minutes and the strength of the ammonium thioglycolatesolution is at a level lower than that of ammonium thioglycolatesolutions used in non-heat-assisted permanent hair waving systems andhigher than that of ammonium thioglycolate solutions used in priorheat-assisted permanent waving systems.

As is well known, ammonium thioglycolate solutions act on thekeratinaceous protein of the hair to effect the splitting of disulfidebonds in the protein and the creation of sulfhydryl groups capable ofbonding to each other upon oxidation to re-create disulfide groups.Distortion of the hair strands by winding the hair around the rollschanges the spatial relationship of sulfhydryl groups so that uponoxidation any particular sulfhydryl group is highly likely to be joinedto a sulfhydryl group other than the one from which it was originallysplit, resulting in the formation of a different molecular structure inthe hair strand and thereby permanently altering its configuration.

The strength of an ammonium thioglycolate solution, or the extent towhich it can effect the desired splitting of disulfide bonds within agiven time at a given temperature is dependent on both its ammoniumthioglycolate content and its alkalinity, stronger solutions havinghigher ammonium thioglycolate contents, higher pH levels, or both.

As is well known in the permanent waving art, human hair variessubstantially in the ease or difficulty of effecting permanent wavingand in its susceptibility to damage by overprocessing, depending on thebasic na ture of the hair and on its processing history. For thisreason, it has been customary, both in cold waving and in heat-assistedwaving to select for a particular hair waving operation one of severalammonium thioglycolate solutions, depending on the nature of the hair tobe treated. The system of the instant invention also provides severalammonium thioglycolate solutions of different strengths and requiresselection from among these several solutions of a single solutionsuitable for a particular head of hair.

It is to be noted, however, that although the several solutions used inaccordance with the present invention differ substantially from eachother in processing strength, each of them is weaker than the comparablesolutions used on the same type of hair in cold waving, and each of themis stronger than the comparable solutions used on the same type of hairin prior heatassisted waving systems in which emphasis was placed onhaving clamps of maximum specific heat and heat content so that thedesired elevated temperature could be maintained as long as possible.

In the instant invention, the clamps are designed to hold a substantialamount of heat but not so great an amount of heat as to retain a hightemperature in the clamps beyond the required processing time. Theclamps are limited in mass by the avoidance of metal inserts of metalparticles, or heavy materials of construction which have been used inprior clamps to maximize heat content. The clamps used in accordancewith this invention are designed to heat wet hair on a roll to atemperature above F. and to maintain it for a period not longer than 6minutes. At temperatures below about 120F. the solutions used aresubstantially inactivated with respect to the particular hair for whichthey are utilized and the danger of overprocessing is obviated. Theclamps used in this invention and the apparatus for heating them aredescribed in the copending and coassigned United States application ofJohn R. Forsberg (one of the coapplicants herein), Ser. No. 382,886,filed July 26, 1973, which application is incorporated herein byreference.

In a typical operation, a clamp used in accordance with this inventionis removed from a rod heated to about 220F. and immediately placed on acurl. The heat retained in the clamp brings the curl up to processingtemperature (about 120F.) in about one to one and one-quarter minutes.The clamp then continues to raise the temperature of the curl to a peaktemperature of about F. and then begins to cool, dropping the curltemperature to a level below about 120F. within 6 minutes afterapplication of the clamp to the curl.

EXAMPLE 1 A specific formulation for use in the heat-assisted waving ofnormal hair comprises:

Ammonium thioglycolate (60% aqueous) 15.1000 parts Water, deionized77.3977 parts Ammonium Hydroxide 0.2800 parts Ammonium Bicarbonate5.4000 parts Fatty acid modified protein 0.5000 parts Perfume 0.2000parts Latex opacifier 1.0000 parts Dyes 0.1223 parts The ammoniumthioglycolate acts to break disulfide linkages in the hair. The ammoniumhydroxide acts as a swelling agent for hair. The ammonium bicarbonate isa buffer. The fatty acid modified protein acts as a carrier for theperfume and also as a penetrating agent for the wetting of the hair bythe lotion.

The above formulation has a thioglycolate content of 9.710.] wt. percent(calculated as thioglycolate ion) and a pH of 76:01

EXAMPLE 2 A specific formulation for use in the heat-assisted waving ofhair which is difficult to process comprises:

13.3000 parts Ammonium thioglycolate (60% aqueous) 78.2890 parts Water,deionized Ammonium hydroxide 1.2720 parts Ammonium bicarbonate 5.4000parts Fatty acid modified protein 0.5000 parts Perfume 0.2000 partsLatex opacifier 1.0000 parts Dye 0.0395 parts The above formulation hasa thioglycolate content of 8.5i0.l wt. percent (calculated asthioglycolate ion) and a pH of 8.4i0.1.

EXAMPLE 3 A specific formulation for use in the heat-assisted waving oftinted hair comprises:

Ammonium thioglycolate (60% aqueous) 4.05 parts Water, deionized 88.81parts Ammonium Hydroxide 1.40 parts Fatty acid modified protein 0.50parts Perfume 0.20 parts Enzyme hydrolyzed protein 4.00 parts Latexopacifier 1.00 parts Dye 0.04 parts The above formulation has athioglycolate content of 2.5i0.1 wt. percent (calculated asthioglycolate ion) and a pH of 9.35-0.05.

EXAMPLE 4 A specific formulation for use in the heat-assisted waving ofbleached hair comprises:

The above formulation has a thioglycolate content of 0.75 wt. percent1005. It has a pH of 7.6i0.1, or should be adjusted to a pH in thisrange by the addition of small amounts of ammonium hydroxide, ifnecessary.

Each of the above formulations, as stated above,

drops off substantially in activity (with respect to the type of hair onwhich it is used) as the clamp loses heat and thus the danger ofovertreating by prolonged exposure is minimized. However, it isnevertheless preferred to remove the clamps after six to eight minutesof exposure and thereafter immediately wash off excess thioglycolatesolution and begin the oxidation process.

Oxidation of the heated hair to restore disulfide bonds is carried outin the same manner as oxidation after non-heat-assisted thioglycolatetreatment. A typical oxidization formulation comprises:

Water, deionized 90.744 parts Fatty acid quaternary ammonium complex3.008 parts Hydrogen Peroxide (35% aqueous) 6.230 parts Phosphoric acidto pH 3.5 app. 0.009 parts Silicone antifoam agent 0.010 parts The fattyacid quaternary ammonium complex is a conditioning agent which serves toimprove the combability of the finished waves.

The formulation provides a hydrogen peroxide content of 7.3 to 7.5volume percent and a pH of 3.5 i 0.1 at F.

It is to be understood that the foregoing examples are intended to bemerely illustrative and that modifications and variations will beapparent to those skilled in the art.

We claim:

1. In a heat-assisted method for the permanent waving of hair in whichan aqueous solution containing ammonium thioglycolate is applied to hairwound around a roll to wet said hair, the wetted hair is maintained atan elevated temperature by a heated clamp holding said hair around saidroll, excess ammonium thioglycolate solution is then removed and anoxidizing solution is thereafter applied to said hair to neutralize saidammonium thioglycolate solution, the improvement which comprisespermitting said heated clamp to heat said wetted hair to a temperatureabove F. and to maintain a temperature about 120F. for no more than 6minutes, and utilizing as said ammonium thioglycolate solution, asolution of greater strength than is used on similar hair in priorheat-assisted permanent waving and of lesser strength than is used inprior non-heat assisted permanent waving, said solution having anammonium thioglycolate content in the range between 0.75 i 0.05 and 9.7i 0.1 weight percent and having a pH in the range between 7.6 i 0.1 and9.35 i 0.05.

2. The method of claim 1 in which said hair is normal hair and saidsolution has a thioglycolate content of 9.7 i 0.1 weight percent and apH of 7.6 i 0.1.

3. The method of claim 1 in which said hair is tinted hair and saidsolution has a thioglycolate content of 2.5 i 0.1 weight percent and apH of 9.35 0.05.

4. The method of claim 1 in which said hair is resistant to permanentwaving and said solution has a thioglycolate content of 8.5 i 0.1 weightpercent and a pH of 8.4 0.1.

5. The method of claim 1 in which said hair is bleached hair and saidsolution has a thioglycolate content of 0.75 i 0.05 weight percent and apH of 7.6 i 0.1.

1. IN A HEAT-ASSISTED METHOD FOR THE PERMANENT WAVING OF HAIR IN WHICHAN AQUEOUS SOLUTION CONTANING AMMONIUM THIOGLYCOLATE IS APPLIED TO HAIRWOUND AROUND A ROLL TO WET SAID HAIR, THE WETTED HAIR IS MAINTAINED ATAN ELEVATED TEMPERATURE BY A HEATED CLAMP HOLDING SAID HAIR AROUND SAIDROLL, EXCESS AMMONIUM THIOGLYCOLATE SOLUTION IS THEN REMOVED AND ANOXIDIZING SOLUTION IS THEREAFTER APPLIED TO SAID HAIR TO NEUTRALIZE SAIDAMMONIUM THIOGLYCOLATE SOLUTION, THE IMPROVEMENT WHICH COMPRISESPERMITTING SAID HEATED CLAMP TO HEAT SAID WETTED HAIR TO A TEMPERATUREABOVE 120*F. AND TO MAINTAIN A TEMPERATURE ABOUT 120*F. FOR NO MORE THAN6 MINUTES, SAID UTILIZING AS SAID AMMONIUM THIOGLYCOLATE SOLUTION, ASOLUTION OF GREATER SSTRENGTH THAN IS USED ON SIMILAR HAIR IN PRIORHEATASSISTED PERMANENT WAVING AND OF LESSER STRENGTH THAN IS USED INPRIOR NON-HEAT ASSISTED PERMENENT WAVING, SAID SOLUTION HAVING ANAMMONIUM THIOGLYCOLATE CONTENT IN THE RANGE BETWEEN 0.75$0.05 AND9.7$0.1 WEIGHT PERCENT AND HAVING A PH IN THE RANGE BETWEEN 7.6 $ 0.1ABD 9.35 $ 0.05.
 2. The method of claim 1 in which said hair is normalhair and said solution has a thioglycolate content of 9.7 + or - 0.1weight percent and a pH of 7.6 + or - 0.1.
 3. The method of claim 1 inwhich said hair is tinted hair and said solution has a thioglycolatecontent of 2.5 + or - 0.1 weight percent and a pH of 9.35 + or - 0.05.4. The method of claim 1 in which said hair is resistant to permanentwaving and said solution has a thioglycolate content of 8.5 + or - 0.1weight percent and a pH of 8.4 + or - 0.1.
 5. The method of claim 1 inwhich said hair is bleached hair and said solution has a thioglycolatecontent of 0.75 + or - 0.05 weight percent and a pH of 7.6 + or - 0.1.